The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 05, 1994
Filed:
Aug. 17, 1992
Glenn M Tom, New Milford, CT (US);
Novapure Corporation, Danbury, CT (US);
Abstract
An in-line detector system for real-time detection of impurity concentration in a flowing gas stream. In a specific aspect, the system may comprise a purifier unit for selective purification of gas from the gas stream, and an impurity addition unit for imparting a predetermined concentration of impurity to the gas stream, whereby the resulting concentration sensings of the purified gas, and the impurity-enhanced gas are usefully employed to calibrate an impurity concentration sensor, for continuous accurate sensing of impurity concentration in the flowing gas stream. The system may utilize hygrometric sensors in the case of water as a critical impurity, or surface acoustical wave (SAW) devices coated with suitable impurity-affinity coatings. The system has particular utility in monitoring low impurity concentration levels (e.g., from about 0.1 ppm to about 100 ppm) in gas streams employed in vapor-phase processes such as chemical vapor deposition in the manufacture of semiconductor devices.